The present invention relates to an automatic apparatus for continuously forming cloth rolls.
More in particular the object of the present invention is to provide an automatic apparatus for forming cloth rolls of the type disclosed and claimed by U.S. Pat. No. 3,782,664.
By the apparatus being the object of the above-mentioned patent, the problem of continuously forming, without any operator's intervention, cloth rolls of a selected constant length has been solved, thus obtaining a particularly high production. The main advantage afforded by such an apparatus, besides the completely automatic operation, resides in the fact of allowing cloth batches to be rolled up directly from rolls of great size, formed with a plurality of pieces of fabric mutually sewn together, which are supplied by a finishing unit. This has allowed a substantial reduction of the dead time required in such a unit for the steps of loading and discharging the rolls formed by the above-mentioned apparatus.
One of the most important advantages of this prior art apparatus has been due to the fact that it allowed obtaining cloth rolls of a reduced length, such as for the rolls generally used by the retailers.
The apparatus according to the present invention allows the same problem to be solved in a more satisfactory manner and in particular, further to eliminate some inconveniences of the prior apparatus, it results to have a more reliable operation and to provide for a higher production, while being of a simplified construction.
According to the basic feature of the apparatus of the present invention, it is provided with means for avoiding the formation of the so-called "fents", i.e. those remnant pieces of cloth which, due to their reduced length, must be sold under cost.
With the prior apparatus, as well as in the one being the object of the above-mentioned patent, it is known that the length of the wound batch of fabric is always the same, since the cutting operation is carried out at prefixed, regular time intervals by control means to be preset. As the feed rate of the fabric can be considered to be constant, it is clear that each cutting operation will be effected when a selected length of fabric has been fed forward. This involves some drawbacks due to the fact that the length of the cloth pieces forming the mentioned great size rolls is not always the same, although its variation range is restricted.
If we suppose to have a big cloth roll of e.g. 5000 m formed with pieces each of 200 m and the apparatus for forming rolls of fabric of shorter length has been preset to effect a cut every 50 m, the cutting operation will be carried out at the predetermined intervals, irrespective of the fact that the cloth is cut or not exactly along the seam between a piece and the following one. In practice, when a cloth piece is actually long 200 m, the apparatus will produce 4 rolls of 50 m each.
If the piece has a length lower than the nominal one, e.g. 195 m, the apparatus will give 4 rolls of 50 m. But on the last cloth roll, at 5 m from its end, there will be the seam of junction with the following piece. Therefore the last 5 m will have to be severed from the roll, thus forming the so-called fent.
If the piece has a length greater than the nominal one, e.g. 205 m, the same drawback occurs. Also in this case the apparatus gives 4 rolls of 50 m which can be used as such, the joining seam being on the following roll at 5 m from its leading edge. It is again necessary to eliminate 5 m of remnant.
In this second example the drawback is also noticed even if the roll obtained is the last because after the last cut carried out by the apparatus, there will be a remnant of 5 m.